19361989 has 4 divisors (see below), whose sum is σ = 19885324. Its totient is φ = 18838656.

The previous prime is 19361959. The next prime is 19362017. The reversal of 19361989 is 98916391.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 14760964 + 4601025 = 3842^2 + 2145^2 .

It is a cyclic number.

It is not a de Polignac number, because 19361989 - 2⁵ = 19361957 is a prime.

It is a super-2 number, since 2×19361989² = 749773236072242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19361939) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 261612 + ... + 261685.

It is an arithmetic number, because the mean of its divisors is an integer number (4971331).

Almost surely, 2^19361989 is an apocalyptic number.

It is an amenable number.

19361989 is a deficient number, since it is larger than the sum of its proper divisors (523335).

19361989 is an equidigital number, since it uses as much as digits as its factorization.

19361989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 523334.

The product of its digits is 104976, while the sum is 46.

The square root of 19361989 is about 4400.2260169223. The cubic root of 19361989 is about 268.5241329956.

The spelling of 19361989 in words is "nineteen million, three hundred sixty-one thousand, nine hundred eighty-nine".